Freight is moved by rail, water, pipeline, truck, and air. The rail network accounts for approximately 40 percent of U.S. freight moves by ton-miles (the length freight travels) and 16 percent by tons (the weight of freight moved). [5]
On the rails, in general, bulk freight, such as grain and coal, ships in rail cars and consumer goods, such as items found at a neighborhood store, ship in containers or trailers called intermodal traffic. Intermodal traffic refers to the transport of goods on trains before and/or after transfers from other modes of transportation such as planes, vessels, or trucks. It has been the fastest growing segment of the freight rail industry since 1980.